1. Field of Invention
This invention relates to a page lifter, and more particularly to a clip-on type of page lifter to be attached to a loose-leaf ring binder in order to prevent the snagging and damaging of loose-leaf pages.
2. Prior Art Discussion
Page lifters designed to eliminate the snagging of loose-leaf pages in ring binders are not new. Most of them consist of two identical page-size sheets joined together with a middle portion which is aligned with the back member or spring cover of the ring binder. Each sheet has at least two apertures transverse to the sheet length and are secured to the rings of the binder. On the lifters, there are provided some raised structures which aid the lifting of the pages fitted on the rings. Such structures are shown in U.S. Pat. Nos. 3,493,310, 3,366,118, 4,573,822, 3,306,301, and 2,639,713. A section of this structure is used in U.S. Pat. No. 3,591,300.
It is to be noted that the page lifters of the prior art all need to be secured to the rings of the ring binder. These page lifters are complicated to manufacture and difficult to use.